The primary structure of the L-chains (lambda) of a myeloma globulin (Mcg) will be correlated with the X-ray diffraction pattern of it obtained by Edmundson et al to determine the relation of the three-dimensional structure to sequence. Lambda-chains of other myeloma proteins and of normal human IgG will be studied to see if the variant features of the new amino acid residues at positions 113 and 115 in McG are allotypic in nature and how they relate to those already noted at positions 190 (Oz) and 154 (Kern). Studies of the binding of other lambda-chain Bence-Jones proteins to Mcg H-chains will be studied and related to those position substituents. Alpha-Fetoprotein of humans and rats will be purified by mild methods to provide material suitable for determinations of its biological role. The primary structure of this protein will be determined. The acitic fluid of rats with hepatomas in the ascites form and fetal rats and humans will serve as source material. The two non-identical peptide chains of superoxide dismutase will be separated by electrical transport in the presence of non-ionic dissociative reagents and their sequence determined. The binding of the zinc and copper moities and the role of the two sluggishly reacting sulfhydryl groups which are involved in the binding of the two chains will be of particular interest. The carbonic anhydrases of human kidneys will be isolated and the variant isoelectric forms noted related to possible amino acid differences with the erythrocyte forms. The effect of antibodies to one form of erythrocyte enzyme on increasing the enzymatic activity of the heterologous form by modifying the depth of the active site crevice will be studied. The variations in the carbonic anhydrases in a given animal to specific amino acid substitutions and their sequence relationships to the normal and mutant forms of the human enzymes will be investigated.